The Holy Grail of researchers in the field of solar photovoltaic (SPV) electricity is to generate it at a lower cost than that of grid electricity. The goal now seems to be within reach.

A Palo Alto (California ) start-up, named Nanosolar Inc., founded in 2002, claims that it has developed a commercial scale technology that can deliver solar electricity at 5 cents per kilowatt-hour.

The breakthrough has come through the application of nanotechnology to create components via molecular self-assembly, including quantum dots (10nm large nanoparticles) as well as nanotemplates with structural order extending through all three dimensions.

In addition, Nanosolar has demonstrated that the three dimensionally engineered nanotemplates can be conformally coated or solidly filled with semiconductor paint to create ultra-thin solar cells with layers that are yet another factor 100x thinner than conventional thin-film amorphous silicon solar cells.

This allows a 10x larger surface area of these structures to be used to achieve a 10x increase in efficiency for such thin layers, thus making it possible to use even less material for similarly efficient cells. Conventional inorganic semiconductors tend to require intricate processing to ensure large grains of crystallinity (in the extreme case: mono-crystallinity) so that charges can travel hundreds of nanometres without getting trapped and lost (at internal crystal boundaries).

Source: The Hindu